This month (it was meant for July, but this came in a little late), a 3 page Unearthed Arcana PDF presents two new options that allow arcane casters to express their faith in the gods. Warlocks get the Pact of the Seeker and Wizards get the Theurgy arcane tradition. As always, remember this material is playtest ready but is likely not perfect.
“For warlock characters, the Pact of the Seeker defines a bond to a mysterious, inscrutable deity dedicated to gathering knowledge and lore. For wizards, the Theurgy arcane tradition creates a magic-user whose arcane instruction is guided by the teachings of a deity, and who gains the benefits of a divine domain.”